Fundamental Analysis of a First Stage Ramjet-Rocket Combined Cycle and Second Stage Hydrolysis Propulsion System with Trajectory Weighting

摘要

A unique first and second stage propulsion system are proposed and defined from a trajectory weighted specific impulse using fundamental performance analysis. The first stage incorporates a combined cycle system utilizing a tandem operated ramjet and rocket propulsion system. Both aspects of the first stage combined cycle use liquid natural gas, which is approximated as methane, as a common fuel source. With respect to oxidizer, the ramjet uses ambient atmospheric air between the bounds of Mach 0.25 and Mach 4, while the rocket uses liquid oxygen. Based on the flight profile of another launch vehicle system, the trajectory weighted specific impulse is acquired, based on the weighted sum of the ramjet-rocket combined cycle and the rocket only aspect of the first stage ascent. Subsequently, the second stage trajectory weighted specific impulse is acquired. The second stage incorporates a hydrolysis propulsion system. The system concepts for both first and second stage along with the foundations for the fundamental performance analysis of both stages are presented. The fundamental performance analysis provides the trajectory weighted performance analysis for the first stage ramjet-rocket combined cycle with the subsequent rocket only mode and the hydrolysis propulsion second stage.